Dental pulp tester

ABSTRACT

A hand-held dental pulp tester comprising in one integral unit means for selectively applying heat, cold, electrical shock and mechanical impact to the tip of the tester which is in contact with a patient&#39;&#39;s tooth.

United States Patent [1 1 Brown Jan. 1, 1974 1 1 DENTAL PULP TESTER [76]Inventor: Ronald W. Brown, 8340 S.W. 65th Ave., Miami, Fla. 33143 [22]Filed: Mar. 16, 1972 [21] Appl. No.: 235,391

[52] US. Cl. ..l28/2.1 R, 128/2 R [51] Int. Cl ..A61b 10/00 [58] Fieldof Search 128/2 R, 303.1, 399,

[5 6] References Cited UNITED STATES PATENTS 3,274,995 9/1966 Eidus128/2 R 3,362,381 1/1968 Farrell 128/3031 X 3,507,283 4/1970 Thomas, Jr.128/3031 3,533,397 10/1970 Sch er 128/399 X 3,702,114 11/1972 Zacariaii128/3031 Primary ExaminerRichard A. Gaudet Assistant Examiner-Lee S.Cohen Alt0rneyRobert G. McMorrow [57] ABSTRACT A hand-held dental pulptester comprising in one integral unit means for se1ective1y applyingheat, cold, e1ectrica1 shock and mechanical impact to the tip of thetester which is in contact with a patients tooth.

5 Claims, 7 Drawing Figures Pmmwm '1 m4 SHEET 2, BF 2 BACKGROUND OF THEINVENTION 1. Field of the Invention The invention relates generally tothe field of human tooth testing, and, more 'particularly, to ahand-held device for selectively applying a plurality of physicalstimuli to patients tooth for the purpose of detecting dental pulpdisease. 4

2. Description of the Prior Art The state of the prior art is reflectedby US. Pat. No. 3,274,995, issued to Eidus and US. Pat. No. 3,533,397,issued to Scher.

The Eidus patent discloses a dental pulp tester having a tip or probe ateach end thereof. Thermoelectric devices within the tester produce heatat one tip and cold at the other tip.

Scher does not relate to a dental pulp tester but rather to a generaldiagnostic instrument for imparting heat,'cold and electric shock to thehuman body for testing the responsiveness thereof to these neurologicalstimuli. This instrument requires two different replaceable tip modulesfor providing the different stimuli to the patients body.

SUMMARY OF THE INVENTION The primary object of this invention is toprovide a completely self-contained hand-held dental pulp tester whichcan selectively apply four different stimuli to a patients tooth inorder, to test the tooth for dental pulp disease.

A more specific object of the invention is to provide such a dental pulptester with manually selectable inde- BRIEF DESCRIPTION OF THE DRAWINGFIG. la is a partial close cross-sectional view of the preferredembodiment of the invention and also shows some components in elevation.

FIG. lb is a cross-sectional view of the tip of the tester.

FIG. 2 is a rear elevational view of the tester illustrated in FIG. la.

FIG. 3 is a partial cross-sectional view showing the details of the coldproducing feature of the invention.

FIG. 4 is a schematic circuit diagram of the heat producing feature ofthe invention.

FIG. 5 is a schematic circuit diagram of the high voltage or electricalshock producing feature of the invention.

FIG. 6 is a partial cross-sectional view showing the details of themechanical impact producing feature of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT able plastic material, such aspolyvinyl. Mounted within the housing for longitudinalmovement relativethereto and projecting from the housing is a stainless steel tube 12covered with insulating plastic and terminating in a metal tip 16. Tip16 is actually the metal housing of a transistor and has a dimple 17 ordepression in its top surface for providing a greater contact surfacewith an irregularly shaped tooth.

Mounted within housing 10 is a copper tank 18 containing liquid butaneunder pressure. As will be described below in more detail with respectto FIG. 3, the outlet of the butane tank is coupled through a valveassembly 20 and a discharge hose 22 to a discharge nozzle 24 mounted onthe tip 16. The discharge hose passes through the interior of the hollowtube 12 and is coupled to the inlet of the nozzle 24. An actuator button26 controls the valve assembly to control the discharge of butane fromthe tank 18. Housing ll) also has an opening 25 for providing access toa recessed butane refill valve 27.

The details of tip 16 are shown in FIG. 1b. The tip is fixed to the endof tube 12 by epoxy cement 31. Mounted in the tip is a heat-producingtransistor which is electrically connected via wires 21 and 23 through aswitch to a pair of 1.4 volt batteries mounted in the lower compartment28 in housing 10. The switch is manually operated by an actuator button29 which projects through housing 10. The metal tip 16 is the transistorhousing which acts as a heat sink for the transistor and as the heatsource of the tester. The details of the heater circuit are shown inFIG. 4.

Another battery in compartment 28 is also connected to a potentiometerthrough a transistorized high voltage generating circuit mounted on acircuit board 30. A calibrated knob 34 may be manually rotated tooperate the potentiometer and control the voltage applied to the tip 16over a range of 0 to 400 volts. The high voltage is applied to tip 16through wires 35 and 23 by the manual operation of a switch buttonactuator 36. A

metal plate 38 fixed to the outside of housing 10 com- I pletes anelectrical path through the patient and the dentist. A neon lamp 39'isconnected in the high voltage circuit and glows when high voltage isbeing applied to the tip of the tester. The details of the high voltagegenerating circuit are shown in FIG. 5.

Also mounted within housing 10 in contact with the lower end of the tube12 is a mechanical impacter assembly 40, the details of which are shownin FIG. 6. An actuating hammer trigger 42 protrudes through a slot (notshown) in housing 10. A hammer reset lever 44 protrudes through a slot46 on the opposite side of housing 10 as shown in FIG. 2.

Turning now to the cold producing mechanism, we see in FIG. 3 thedetails thereof. The copper tank 18 contains a reservoir of liquidbutane 50. The lower end of a wick filled with plastic foam is submergedin the liquid butane and the upper end of the wick is coupled to thevalve assembly 20. The cold actuator button 26 projects through anopening in the housing 10. When the button is manually pushed inwardly,its cam surface bears upwardly against projection 51 to rotate a releaselever 52 around a fulcrum 53 to open the valve assembly 20, so that someof the liquid butane is allowed to escape via the wick and is conductedvia the discharge hose 22 to the tip 16 of the tester. The liquid butaneis stored under pressure in tank 18. Because of the latent heat ofvaporization of such a liquid, when the liquid is released from the tankand is no longer under pressure,

it evaporates to cool its immediate surroundings, which in this caseincludes the-tip 16 of the pulp tester.

FIG. 4 illustrates a schematic circuit diagram of the heater. A 2N3505transistor 56 is connected in series with a 2.8 volt battery 58 and aswitch 60 which is closed by the manual operation of the hot actuatorbutton 29. The voltage is actuallysupplied by two 1.4 cells connected inseries. The metal tip 16 of the tester is the transistor housing or casewhich supplies heat to the patients tooth when the switch is closed.

A schematic circuit diagram of a high voltage generating circuit isillustrated in FIG. 5. This circuit is a conventional free runningmultivibrator which converts an 8 volt DC voltage into a 400 voltpeak-to-peak AC voltage. The 8 volt battery 62 is connected through thehigh voltage switch 64 to the transistorized multivibrator circuit 66.The AC output from the circuit is developed across the transformer 68which in turn is connected across the potentiometer 32. The wiper arm 70of the potentiometer is mechanically connected via a shaft 72 to thevoltage adjusting knob 34 on the housing 10. The neon lamp 39 isconnected across the secondary of transformer 68 and is energizedwhenever the high voltage appears across the transformer. The highvoltage generating circuit is energized by pushing the high voltageswitch button actuator 36 which closes the switch 64, and applies thevoltage to tip 16 via the wires 35 and 23.

FIG. 6 shows the details of the mechanical impacter assembly 40. Theassembly comprises an impacter case 80 having a slot 82 through whichthe trigger 42 for a hammer 84 projects. There is a corresponding slotin the housing of the tester to permit the trigger 42 also to projectthrough the housing so that it can be manually operated by the dentist.The impacter assembly is similar to a single action pistol. The fullline positions of the trigger and hammer represent the cocked positionof the assembly.

Trigger 42 is pivoted on a fulcrum 86 and biased in aclockwise-direction by a spring 88. The hammer 84 is pivoted on afulcrum 90 and is biased in a counterclockwise direction by a spring 92.In this cocked position, the inner end of the trigger engages a notch inthe hammer to prevent release of the hammer. However, when the triggerhandle is depressed to the dotted line position, the hammer 84 isreleased to rotate upward to its dotted line position so that its flatsurface 94 imparts a short, quick impact to the lower end 96 of tube 16.This lower end is solid, and a retaining pin 98 passes through a boss100 of housing 80 and through an elongated hole 102 in the tube s lowerend 96, thereby permitting the tube to move sharply upwardly to providean impact to a patients tooth engaged by the tip 16. To recock theassembly, the reset lever 44 is rotated clockwise through slot 104against the action of spring 92, until both the trigger and hammer arereturned to their full line positions, where the hammer is again lockedin the cocked position by the spring-biased trigger.

From the foregoing description, it is seen that I have invented a noveldental pulpte ster which incorporates in a single hand-held instrumentmeans for selectively providing a plurality of stimuli to a patientstooth in order to test for dental pulp disease. These stimuli are heat,cold, electrical shock and mechanical impact. Furthermore, all of thesestimuli are provided by an integral structure which does not require thereplacement of components thereof to provide the different stimuli.Pieces of suitable material, such as polyvinyl chloride, are glued tovarious parts of the tester housing in order to retain the transformer,batteries and other components in their proper positions.

5 While the invention has been particularly shown and described withreference to the preferred embodiment thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the spirit and scope of 10 theinvention.

nozzle;

f. a normally closed pressure release valve means coupled between saidconduit and said container; g. cold actuator means mounted on saidhousing for opening said valve means to permit cold coolant vapor to bedischarged through said conduit to said tip; h. electric heating meansmounted in said tip; i. means for mounting a battery in said housing; j.terminal means in said housing for making electrical contact with abattery mounted in said housing;

k. normally open switch means connected between said terminal means andsaid electric heating means;

1. heat actuator means mounted on said housing for 3 5 closing saidswitch means to energize said heating means and heat said tip;

m. high voltage generating means connected between said terminals andsaid heating means;

n. a normally open high voltage switch connected between said terminaland said high voltage generating means; and r o. a high voltage actuatormounted on said housing for closing said high voltage switch to applyhigh voltage to said tip.

2. A hand-held dental pulp tester as defined in claim furthercomprising:

a. hammer means mounted in said housing and operable to impart suddenmotion to said tube along said longitudinal axis thereof and relative tosaid housing; and

b. trigger means mounted on said housing for operating said hammermeans. 3. A hand-held dental pulp tester as defined in claim 1 whereinsaid coolant is liquid butane and further comprising a wick having oneend submersed in said butane and the other end coupled to said valvemeans.

4. A hand-held dental pulp tester as defined in claim 2 furthercomprising:

a. a potentiometer connected between said high voltage generating meansand said tip; and

0 b. manually operable voltage adjusting means mounted on said housingand mechanically connected to said potentiometer for adjusting thevoltage applied to said tip.

5. A hand-held dental pulp tester as defined in claim 4 furthercomprising a high voltage indicating lamp connected to said high voltagegenerating means for indicating the application of voltage to said tip.

1. A hand-held dental pulp tester comprising: a. a housing; b. a rigidtube mounted in said housing for movement along the longitudinal axis ofsaid tube and extending therefrom and terminating in a tip; c. a nozzlemounted in said tip; d. a pressurized container of vaporizable coolantmounted in said housing; e. a conduit coupled between said container andsaid nozzle; f. a normally closed pressure release valve means coupledbetween said conduit and said container; g. cold actuator means mountedon said housing for opening said valve means to permit cold coolantvapor to be discharged through said conduit to said tip; h. electricheating means mounted in said tip; i. means for mounting a battery insaid housing; j. terminal means in said housing for making electricalcontact with a battery mounted in said housing; k. normally open switchmeans connected between said terminal means and said electric heatingmeans; l. heat actuator means mounted on said housing for closing saidswitch means to energize said heating means and heat said tip; m. highvoltage generating means connected between said terminals and saidheating means; n. a normally open high voltage switch connected betweensaid terminal and said high voltage generating means; and o. a highvoltage actuator mounted on said housing for closing said high voltageswitch to apply high voltage to said tip.
 2. A hand-held dental pulptester as defined in claim 1 further comprising: a. hammer means mountedin said housing and operable to impart sudden motion to said tube alongsaid longitudinal axis thereof and relative to said housing; and b.trigger means mounted on said housing for operating said hammer means.3. A hand-held dental pulp tester as defined in claim 1 wherein saidcoolant is liquid butane and further comprising a wick having one endsubmersed in said butane and the other end coupled to said valve means.4. A hand-held dental pulp tester as defined in claim 2 furthercomprising: a. a potentiometer connected between said high voltagegenerating means and said tip; and b. manually operable voltageadjusting means mounted on said housing and mechanically connected tosaid potentiometer for adjusting the voltage applied to said tip.
 5. Ahand-held dental pulp tester as defined in claim 4 further comprising ahigh voltage indicating lamp connected to said high voltage generatingmeans for indicating the application of voltage to said tip.